This research investigates the perceptions of hill tribe people in Northern Thailand of the sociocultural impacts and changes in their communities resulting from the interaction between themselves, their communities and the incoming mainly Thai, origin, external tourism actors (ETAs), such as tourism authorities, tourism businessmen / investors and tour operators. In Thailand, most studies on the impacts of tourism have been limited to economic analyses, and the socio-cultural impacts of tourism on hill tribe people has been under-researched. Of the previous studies of the socio-cultural impacts of tourism, the majority have examined the impacts from host and guest interactions, emphasising the negative social impacts resulting from the influx of tourists in general. Specific research on the interaction of local hill tribe people with incoming ETAs has not been reported. To fill this gap, this research aims to compare the perceptions of two hill tribe peoples (the Karen and Hmong), both those working for ETAs and those who do not, in terms of their employment experiences and perceived socio-cultural impacts resulting from the arrival of ETAs. In order to achieve the research aim, a combination of qualitative and quantitative methods was used. A sequential approach was adopted incorporating a mixed methods design in order to better answer the research challenge of exploring the participants' views and perceptions. Building on a thorough literature review the first phase of primary data collection adopted a qualitative approach. Focus groups were used to explore the local hill tribe perceptions towards the interaction between ETAs and themselves, and their perceptions towards socio-cultural impacts upon themselves and changes in their community. Then semi-structure interviews were used to gain more in-depth details from selected participants. Themes from this qualitative phase were then used in the second stage of primary data collection to develop an essentially quantitative questionnaire, to measure, by means of a large scale survey, the perceptions of the selected population. The fmdings suggest that exposure to the social and cultural characteristics of ETAs, have significantly influenced some of the values, beliefs and lives of tribal people. However, despite the impacts resulting from the arrival of ETAs, these hill tribe people tend to be in favour and perceive these impacts and changes as positive changes. Moreover, the fmdings also suggest that differences in ethnic background, working environment and gender can be factors that influence perceptions of these hill tribe people. However, each factor, ethnicity, working environment, gender, exerts differing degrees of influence upon the perceptions of these hill tribe people toward different issues regarding impacts from ETAs. In addition, individual's perceptions toward impacts from ETAs differ despite their having the same ethnic background. However, the evidence gathered suggests that ethnic background does still control, to a degree, these differences with the result that while people's perceptions do differ in many ways nevertheless those from the same ethnic background tend to show greater similarities in their perceptions and actions when compared to those of different ethnicities. To this end, this study has pointed out several recommendations for future research together with the implications of the findings from this research on tourism management and policy makers.